Newtonian and non-Newtonian viscosity of supercooled liquid in metallic glasses

Citation
Y. Kawamura et al., Newtonian and non-Newtonian viscosity of supercooled liquid in metallic glasses, MAT SCI E A, 304, 2001, pp. 674-678
Citations number
24
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Material Science & Engineering
Journal title
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
ISSN journal
0921-5093 → ACNP
Volume
304
Year of publication
2001
Pages
674 - 678
Database
ISI
SICI code
0921-5093(20010531)304:<674:NANVOS>2.0.ZU;2-1
Abstract
We have investigated the viscosity of the supercooled liquids over a wide r ange of strain rate by constant-strain-rate: tensile tests for La55Al25Ni20 , Zr65Al10Ni10Cu15 and Pd40Cu40P20 (at.%) metallic glasses. The supercooled liquids exhibited Newtonian viscosity (equilibrium state) that transferred to a non-Newtonian viscosity (non-equilibrium state) with increasing tempe rature. The critical strain rate of the Newtonian viscosity increased with increasing temperature in accordance with the Arrhenius relation. The strai n rate dependence of viscosity was described well with a master curve expre ssed by a stretched exponential function eta/eta (0) = 1 - esp(C/epsilon (b eta)). The Newtonian viscosity was successfully described with the fret-vol ume model of Cohen and Grest. The fragility of the Newtonian viscosity reve aled that the supercooled liquids of the metallic glasses were classified i nto the relatively strong liquids such as Ge10As10Se80, B2O3 and Na2O-2SiO( 2) glass formers. (C) 2001 Elsevier Science B.V. All rights reserved.